The present invention relates to film unit picking device which is applied to an instant camera or a printer using a self-developing type film unit loaded in a cassette.
In a camera using a mono-sheet type self-developing film unit, which is also called integral or non-peel apart self-developing film unit, (hereinafter simply referred to as xe2x80x9cfilm unitxe2x80x9d), upon finishing exposure, a film unit picking claw moves in a slot formed in a peripheral flange, defining an exposure aperture, of a cassette of a film pack to advance the film unit through the exit of the cassette into a bite of a pair of processing liquid spread rollers. The pair of rollers further advances the film unit out of the camera body while,spreading the processing liquid within the film unit.
Japanese Laid-open Patent 054680/96 (tokkai-hei 08-054680) assigned to Fuji Photo Film Co., Ltd discloses an instant camera with a film unit picking claw swingably mounted on a sliding plate where the picking claw is spring-based toward the film unit to securely engage the film unit for its reliable advancing. However, such a spring-based picking claw tends to cause a problem that the portion of the film unit where the picking claw is urged against is given a deformation which subsequently decreases a gap between the film unit and the adjacent one when a film unit or stacked film units in the cassette accommodated in the camera is left for a long time without being used or under a high-temperature condition. Such deformation of the film unit makes it difficult to securely pick the exposed film unit to advance, and typically causes engagement with two adjacent film units together resulting in failure of processing and discharging the film unit.
An object of the invention is to provide an improved picking claw device described as follows to resolve the aforementioned problems caused by the film unit deformation and to discharge an exposed film unit without fail.
A film unit picking device comprises a picking claw for engaging an edge of a film unit loaded in a film unit cassette, subsequent to exposure by an exposure unit, and advancing the film unit into a bite of a pair of processing liquid spread rollers, wherein the picking claw can be shifted between a first position at which the picking claw is off or slightly touched to the film unit and a second position at which the picking claw can be engaged with a trailing edge of the film unit in association with the movement of the claw to advance the film unit.
The picking claw is mounted on a sliding member being capable of reciprocally moving in a film unit advancing direction and being urged toward the film unit to be engaged with by a biasing member such as a spring disposed between the sliding plate member and the picking claw.
Also a stopping member is formed on a wall and the like located close to the picking claw which is capable of being engaged with the picking claw to prevent the claw from being urged against the film unit and capable of being disengaged from the picking claw in connection with the movement of the claw to advance the unit. The stopping member and a portion incorporated with the claw cooperate with each other to keep the picking claw at the first position by engaging each other.
A first type of stopping member is made of a projection formed on the wall of a film unit receiving chamber, the projection is located in a position where the picking claw can be engaged therewith when it stays in the first position and the picking claw can be disengaged when it moves in the film unit advancing direction.
A second type of stopping member is formed on the exposure unit so that the stopping member and the picking claw can be disengaged when the exposure unit moves for preparation before exposure or for starting exposure.
A third type of stopping member is formed on the exposure unit so that the stopping member and the picking claw can be disengaged when the exposure unit moves for preparation before exposure or for starting exposure.
A fourth type of stopping member is formed on the lens barrel 20 so that the stopping member and the picking claw can be disengaged when the lens barrel is moved to extend from the camera body.
A fifth type of stopping member is formed on a exposure head so that the stopping member and the picking claw can be disengaged when the exposure head is moved to scan the film unit for exposure. The exposure head is moved by a scanning mechanism along the surface of the film unit to make a print in a printer using an instant photographic film unit or an electronic camera with that printer.
Those film unit picking devices can prevent a deformation of the film unit caused by a long-term or under-the-high-temperature-condition urging by the spring-biased claw.